5,746 research outputs found

    Generalized vegetation map of north Merrit Island based on a simplified multispectral analysis

    Get PDF
    A simplified system for classification of multispectral data was used for making a generalized map of ground features of North Merritt Island. Subclassification of vegetation within broad categories yielded promising results which led to a completely automatic method and to the production of satisfactory detailed maps. Changes in an area north of Happy Hammocks are evidently related to water relations of the soil and are not associated with the last winter freeze-damage which affected mainly the mangrove species, likely to reestablish themselves by natural processes. A supplementary investigation involving reflectance studies in the laboratory has shown that the reflectance by detached citrus leaves, of wavelengths lying between 400 microns and 700 microns, showed some variation over a period of seven days during which the leaves were kept in a laboratory atmosphere

    Raman spectroscopy of iodine-doped double-walled carbon nanotubes

    Get PDF
    We present a Raman spectroscopy study of iodine-intercalated (p-type-doped) double-walled carbon nanotubes. Double-walled carbon nanotubes (DWCNTs) are synthesized by catalytic chemical vapor deposition and characterized by Raman spectroscopy. The assignment of the radial breathing modes and the tangential modes of pristine DWCNTs is done in the framework of the bond polarization theory, using the spectral moment method. The changes in the Raman spectrum upon iodine doping are analyzed. Poly-iodine anions are identi- fied, and the Raman spectra reveal that the charge transfer between iodine and DWCNTs only involves the outer tubes

    Dynamics of single polymers under extreme confinement

    Full text link
    We study the dynamics of a single chain polymer confined to a two dimensional cell. We introduce a kinetically constrained lattice gas model that preserves the connectivity of the chain, and we use this kinetically constrained model to study the dynamics of the polymer at varying densities through Monte Carlo simulations. Even at densities close to the fully-packed configuration, we find that the monomers comprising the chain manage to diffuse around the box with a root mean square displacement of the order of the box dimensions over time scales for which the overall geometry of the polymer is, nevertheless, largely preserved. To capture this shape persistence, we define the local tangent field and study the two-time tangent-tangent correlation function, which exhibits a glass-like behavior. In both closed and open chains, we observe reptational motion and reshaping through local fingering events which entail global monomer displacement.Comment: 22 pages, 18 figures, slightly extended version to appear in JSTA

    Reading the High Court at a Distance: Topic Modelling the Legal Subject Matter And Judicial Activity of the High Court of Australia, 1903–2015

    Full text link
    In this article we apply the method of quantitative textual analysis known as ‘topic modelling’ to a significant Australian legal text corpus: that of judgments of the High Court of Australia from 1903 to 2015. The High Court of Australia has been a perennial topic for study and analysis. It is the highest court in the Australian judicial hierarchy and the site of many of the most significant contests of legal doctrine and practice in Australian history. We find that the topic models generated by this research enable the development of a range of unique, novel and robust observations of the High Court’s judicial workload and the shifting make-up of its legal subject matter over time. Moreover, this article reveals the feasibility and value of topic modelling as a method for the study of legal texts and practices that might fruitfully complement other methods of legal scholarship

    Estimation des variations géométriques de grains anisotropes dans un modèle booléen.

    Get PDF
    International audienceLa géométrie stochastique a pour objet l'étude de modèles spatiaux aléatoires dans l'espace euclidien. De nombreux matériaux peuvent être modélisés par des ensembles aléatoires. En effet l'hétérogénéité des matériaux peut être appréhendée par une approche probabiliste, particulièrement les milieux granulaires et fibreux. La compréhension des mécanismes d'agrégation de particules revêt une grande importance dans de nombreux domaines d'application. Plus particulièrement, les processus de cristallisation de particules solides en suspension dans un milieu liquide sont une des préoccupations du LGF(UMR CNRS 5307), l'objectif étant de caractériser les particules en terme de taille, de forme et de répartition spatiale. Ces structures peuvent être naturellement représentées par des réunions de particules aléatoires (les grains) centrées sur des positions aléatoires (les germes), connue sous le nom de modèle germes-grains
    • …
    corecore